Machine for flame-cutting circles



March 1, 1949. MlLLlg 2,463,408

MACHINE FOR FLAME CUTTING CIRCLES Filed Oct. 3, 1946 v 3 Sheets-Sheet l March 1, 1949. s 2,463,408

MACHINE FOB FLAME CUTTING CIRCLES Filed 001;. s, 1946 z-sheets-sheet 2 I I l l l I l l i l l I 1 -March 1,1949. L. MILLIS 2,463,408

MACHINE FOR FLAME CUTTING CIRCLES Filed Oct. 3, 1946 i 5 Sheets-Sheet f5 Patented Mar. 1, 1949 MACHINE FOR FLAME-CUTTING CIRCLES Lansing Milli's, Ben Avon, Pal, assigrror t'o American Bridge Company, a corporation of New Jersey Application October 3, 1946, "SerialNo. 701,037

2 Claims. 1

The present invention relates to features of des'ignand arrangement of flame cutting apparatus designed to cut one or morecircular kerfs simultaneously in a metal plate or similar workpiece. The invention will be fully apparent from the following description when read in connection with the accompanying drawings, and the novel features will be defined with particularity in the appended claims.

In the drawings:

Figure 1 is an end elevation of a machine embodying the invention- Figure 2 is a view partly in side elevation with parts sectioned off as indicated by the staggered line II-II of Figure 1.

Figure 3 is -a horizontal section on staggered line IIIIII of Figure 2.

Figure 4 is a horizontal section on staggered line IV--IV of Figure 2.

Referring in detail to the drawings, in represents the :bed of the machine to which is secured a vertically adjustable work-supporting table I2 of any conventional form. Spaced laterally from the table I2 there is an upright fixed pedestal l4, whichnear its upper extremity carries a journal pin [6 on which is rotatably mounted the hub l8 of a radial arm having upp r and lower members 20 and 22, respectively. -A spring loaded latch 24 coacts with the notch 26 formed in the hub l8 for releasably holding the radial arm in working position.

A hollow vertical shaft 28 is rotatably supported in suitable bearings carried by the members 20 and 22 of the radial arm. This shaft at its lower end has secured thereto a bracket 30 having an arm 32 offset as illustrated in Figure 2 so as to support a torch-carrying bar 34 in such manner that its axis is horizontal and slightly offset laterally from the vertical axis of the hollow shaft 28.

Secured to the bar 34 and extending longitudinally thereof there is a rack 36 which is adapted to enact with pinions 38 and 40 carried by the torch carriages 42 and 44, respectively. Mounted for vertical adjustment in these carriages there are respective flame cutting torches 46 and 48, which have racks 46a and 48a secured thereto, adapted to be vertically adjusted by a manipulation of pinions 46b and 48b. The flame cutting torches 46 and 48 are of conventional form and at their lower extremities they each include a blow pipe nozzle adapted to direct a cuttingflame toward the workpiece supported on the table l2. By suitably manipulating the pinions 38 and 40 it is apparent that the torches 46 and 48 can-be adjusted so as to simultaneously cut circles of different radii, and because the arm 32 secured to the lower end of the bracket 30 is offset from the vertical axis of the shaft'28, as shown in Figure 1, the nozzle of the torch 48 can be moved to a position coincident with the axis of said shaft 28.

Acentering' device, including a bracketio and centering pin '52, is removably secured'by a clamp screw '53 to'the offset bracket 32. The rod 52 is adjustably secured by means of a winged screw 54, which "enters a tappedhole in a lug 56, extending outwardly from the 'bracket as shown in Figure 1. The bracket 50 carrying the centering pin 52 is adapted to be moved to a position clear of the torch carriage "44 when the latter is positioned for flame cuttinga hole in the center of the workpiece coinciding with the axis of the vertical shaft 28. It Will be understood that when the centering pin 52 is lowered, the pointed end thereof may be made to coincide with a center marked on the piece to to be cut; thus assuring that the center of rotation will be axially aligned with the marked center of the workpiece. After the work has been so centered on the table l2, the torches "4'6 and 48 may be adjusted to predetermined radial distances so as to simultaneously flame cut two concentric circular kerfs of the same or different radii in the workpiece. After the torches have been set to the desired radial positions, the shaft 28 is caused to rotate by energizing a motor 58, which acting through a suitable speed reducer, rotates a friction drive wheel 60, the peripheral edge of which bears on a circular table 62 secured to the radial arm 22. The motor 58 and the friction driving wheel 60 are jointly supported by an angular bracket 64 which is pivotally mounted by trunnion studs 66 carried by the vertical shaft 28. Although power can be applied to the vertical shaft 28 by various means, I prefer to use a variable speed motor, such as shown at 58 for driving a friction disc 60. The motor will be connected to conventional reduction gearing through a suitable clutch which will permit free wheeling.

The pipes g and 0 which supply gas and oxygen to the torches, and also the conductor 0 which supplies current to the motor, are conveniently led downwardly through the center of the hollow vertical shaft 28 and are supported overhead within the looped portions 10 and 12 of a radial bracket 14, having a downward ex tension 16 whose lower end is secured at 18 to the hub 18 of the radial arm.

The speed of the motor 58 will be controlled by a conventional device 68. Speeds other than those provided by the motor control device 68 may be made available by varying the size of the friction disc 60. For example, a disc of decreased size can be substituted for the one shown and the tread plate 62 slightly raised. The friction disc 60 is held in contact with the tread surface of the table 62 by weight of the motor and assembly, and thus provides sufficient traction to rotate the flamecutting torches 46 and 48 in their respective circular orbits. For convenience in setting up and removing the work from the table l2, the radial arm 22 can be swung about the vertical axis of the pedestal 14 so as to permit free access to the Work table.

From the foregoing it will be apparent that the improved apparatus disclosed provides means whereby kerfs corresponding to concentric circles may be quickly and easily flame cut through a metal plate or other workpiece, and also provides means whereby the radii of one of the circles can be varied from zero to a maximum radius, limited only by the length of the bar 34. The apparatus is of compact, rugged construction and requires a minimum amount of maintenance and repair to keep it in fit operating condition.

While I have described quite precisely a preferred embodiment of the invention, it is not to be construed that I am limited thereto since various changes in arrangement and substitutions of equivalents may be made by those skilled in the art without departure from invention, as defined in the appended claims.

What I claim is:

1. A flame cutting machine comprising a horizontal table adapted to support a flat workpiece, a vertical pedestal spaced from said table, an arm carried by said pedestal and overhanging said table in spaced relation thereabove, a vertical shaft journaled in said arm, a bracket attached to the lower end of said shaft, the lower end of said bracket being offset from the rotational axis of said shaft in two directions perpendicular to each other, a horizontal supporting bar carried by the lower end of said bracket, a cutting torch carried by said bar and being horizontally adjustable therealong and adapted to cut workpieces on said table, said cutting torch being inset from said bar a distance equal to the offset of said bar from the rotational axis of said shaft, a centerpiece carried by said bracket along the rotational axis of said shaft and being removable to enable said cutting torch to be adjusted to positions fully beneath said shaft, and means for rotating said shaft.

2. A flame cutting machine comprising a horizontal table adapted to support a fiat workpiece, a vertical pedestal spaced from said table, an arm pivoted to said pedestal and overhanging said table in spaced relation thereabove, a vertical shaft journaled in said arm, a. bracket attached to the lower end of said shaft, the lower end of said bracket being offset from the rotational axis of said shaft in two directions perpendicular to each other, a horizontal supporting bar carried by the loWer end of said bracket, a cutting torch carried by said bar and adapted to cut workpieces on said table, said cutting torch being inset from said bar a distance equal to the offset of said bar from the rotational axis of said shaft, a continuous rack on said bar, a pinion on said torch cooperable with said rack for adjusting said torch horizontally along said bar, a centerpiece carried by said bracket along the rotational axis of said shaft and being removable, said bar being free of obstructions from its extremity to its point of attachment to said bracket when said centerpiece is removed so that manipulation of said pinion adjusts said torch to all positions along said bar including a position fully beneath said shaft, and means for rotating said shaft.

LANSING MILLIS.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS FOREIGN PATENTS Country Date Great Britain (1912) Jan. 3, 1913 Germany Aug. 8, 1925 Number Number 

